Content may be selected and delivered to users based on user demographics, allowing advertisers and content providers to provide content that users may be most interested in. While users may be explicitly identified in some instances, in many implementations, users may be implicitly identified as associated with a device or application session. When correct, such application sessions may be referred to as canonical or conforming to the association between user and session. However, the implicit identifications may be incorrect, particularly in instances where users loan devices to each other. Such sessions may be referred to as non-canonical or non-conforming. Content may be mis-selected in such instances, or selected for the wrong user.